Behavioural responses and changes in some haematological parameters of the Cichlid fish, oreochromis niloticus, exposed to trivalent chromium

الملخص EN

Specimens of Oreochromis niloticus were exposed to different concentrations (17.5-27.5 mg/1) of trivalent chromium in the form of CrCl3.

Lc.

50 for 96 h was computed as 23.7 mg/1.

The fishes exposed to sublethal concentrations (3.0 and 6.0 mg/1) showed remarkable changes in behaviour like cough, yawn, fin flickering, jerking movement, nudge and nip.

A positive dose-response relationship was demonstrated for these changes in behaviour.

Frequency of occurrence of such behavioural changes was more pronounced in the beginning of treatment and decreased gradually by prolongation of time, but remained higher than the control.

Changes in haematological parameters such as total leucocyte and erythrocyte counts, haemoglobin and haematocrit were apparent in the fish exposed to trivalent chromium.

The response of fish to chromium was dose dependent.

MCH and MCHC values were significantly affected (P < 0.001).